Method of manufacturing relief geographical maps



NITED STATES PATENT.

FICE.

FREDERICK 'r. BURGI, OF ROCHESTER, NEW YORK, ASSIGNOR T FREDERICK A.LORENZ, OF CHICAGO, ILLINOIS.

METHOD OF MANUFACTURING RELIEF GEOGRAPHICAL MAPS.

SPECIFICATION forming part of Letters Patent No. 537,003, dated April 9,1895. Application filed September 25, 1893. Renewed December 3, 1894-Serial No. 530,742. (No specimens.)

To all whom it may concern:

Be it known that I, FREDERICK T. BURGI, of Rochester, in the county of.Monroe and State of New York, have invented certain new and usefulImprovements in the Method of Manufacturing Relief Geographical Maps andI do hereby declare the following to be a full, clear, and exactdescription of the same, which will enable those skilled in the art toIo practice the invention.

My invention. has for its object to provide a new method ofmanufacturing geographical maps or globes in relief, showing theelevations and depressions Of the earths surface, though welladapted, aswill be understood, to the manufacture of other molded objects ofirregular contour, and it consists in certain improvements inconstruction, as will be hereinafter fully specified and the novelfeatures pointed out particularly in the claims at the end of thisspecification.

In carrying out my invention I first model in some suitable material,preferably wax or other plastic composition, an accurate representationor topographical model for the map to be produced, being a relief mapitself, or

' this may be accomplished by building up,

upon a suitably printed map, the various elevated portions of the earthssurface indicat- 0 ing accurately the various topographical features ofthe country or section, and from this map or pattern I produce bycasting or otherwise a mold or female die, preferably of plaster ofparis, from which, if desired, I produce,

5 by casting a suitable male die. I then take a sheet of ordinaryprinting paper, upon which is printed or otherwise marked a correct flatmap, preferably suitably colored, of the country of which a relief mapis desired, and soak said paper in a solution prepared substantially asfollows, for about fifteen or eighteen hours, sufficiently tothoroughlyimpregnate the paper, but insufficiently to cause its dis-"integration. This solution is prepared as follows:To five gallons ofwater I add one-half pound of alum, one spoonful of vinegar, and onespoonful of granulated white soap, boil this solution for about one-halfhour and then allow it to cool. The vinegar may be omitted from thissolution, but I prefer to employ it.

ing of the ingredients.

After soaking the paper in this solution for from fifteen to eighteenhours, as before mentioned, I remove it therefrom and allow it to drainuntil about half dry. Then, while damp itis placed over the female dieor mold and the parts printed on the map caused to accurately registerwith the corresponding parts one-half hour, which will insure thethorough dissolving of the glue and the thorough mix- This compound isthen placed over the rear side of the map, While over the mold or die,to the depth of about one-fourth of an inch and may be pressed down byhand, causing the paper and composition to be pressed into and fill thedeepest parts of the mold, (that is, the parts 7 5 constituting thehighest portions of the complete map) after which the compound is workedwith the fingers until it is of a uniform thickness on the paper. Themap is then allowed to dry in the mold and is finally removed, attachedto a suitable frame'or backing, appropriately colored if desired, andvarnished. Instead of pressing the composition on the rear of the map byhand the male die or mold 8 5 may be employed instead, and a stop for limiting the approach of the dies, which will insure uniformity inthickness of the backing of plastic material, but if no stops wereemployed the limited quantity of material used would cause this, if itsescape at the sides were prevented, and the map may then be dried whilebetween the mold-sections, but this operation performed in this waywill, of course, require a longer time for drying. 5

The solution in which the paper is soaked enables the paper to bestretched sufficiently to fill the interstices of the mold or diewithout tearing, and the employment of soap in the solution enables itto slide and draw I00 easily over the projections without tearing,though, of course, this object could be accomplished by applying oil orsome similar material to the face of the die or mold, in which event,however, it would be more difficult to varnish or paint the surface ofthe map when completed.

By proceeding in the manner described, relief maps may be easily andcomparatively cheaply made, without the necessity heretofore existing,of first forming the relief map in paper, papier mach, or similarmaterial, and then painting or printing the names of the rivers, lakes,cities, &c., upon it, as these are of course indicated upon the printedmap, which is formed into the topographical map.

\Vhile I prefer to employ the solution and the plastic compositionherein described, asI have found them well adapted for the purpose andcapable of producing excellent results, I do not wish to he confined toexactly the proportions or ingredients described, as they could bemodified to some extent without departing from the spirit of myinvention; as for instance, other plastic materials than whiting andplaster of paris, and other binding materials than flour and glue couldbe used, but, as stated, I prefer these as I have used them withsuccess, and they are comparatively inexpensive.

\Vhen employing the male and female dies in producing maps, I prefer toplace a piece of tissue or similar thin paper over the plasticcomposition to prevent its adhering to the male die and also to submitthe map and plastic composition to pressure between the dies for aboutfive hours, as I find that the best results are produced by this methodof procedure.

The map thus produced has as a support for the printed paper only a thinshell of composition that is not rigid enough to be readily fractured bya blow, but is light and sufficiently rigid for all practical purposes,and is made in such a Way that all the parts of the map in high reliefare faithfully reproduced.

I claim as my invention- 1. The herein described method of making reliefmaps consisting in forming a mold or die exhibiting the topographicalfeatures of the country, then placing over this a map suitably printedand rendered pliable by soaking in a solution of alum and soap, causingthe parts of the map to register with those in the mold, then coveringthe back of the paper map with a plastic composition capable ofhardening, pressing the composition and map into the mold, and dryingit, as set forth.

2. The herein described method of making relief maps consisting informing a mold or die exhibiting the topographical features of thecountry, then placing over this a map suitably printed and renderedpliable, causing the parts of the map to register with those in themold, then covering the back of the map with a plastic compositioncomposed of whiting, plaster of paris, flour and glue, press ing the mapand composition in the mold, and drying the whole, as set forth.

FREDERICK 'l. BURGI.

Witnesses:

FRED F. CHURCH, GRACE A. Rona.

